The actress put on 40lbs before giving birth to daughter Olive 10 weeks ago but isn't worried about dropping the weight quickly because she wants to spend all her time with her little girl rather than in the gym.
She said: "My new motto is 'Impossible expectations are impossible. Look, with my luck I will starve myself, work out and then the next day get hit by a bus. And think 'Why did I waste my time doing that?' I'm the last person anyone should look to for workout tips, I don't have them. I don't care."
Drew - who married husband Will Kopelman while she was pregnant - also revealed she keeps herself busy with trying to make Olive smile.
The 37-year-old actress told People magazine: "My favorite time of the day with her is when I wake her up. Her first smiles are just the greatest. And I'll jump up and down and dance and sing as much as it takes to get those smiles."
The full interview with Drew and exclusive photos of the actress with her family are available in this week's issue of People magazine.